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Discussion Starter #1
When i pull my engine to do a rebuild this summer, i want to end up with a low compression ratio (hopefully under 9.5 possibly under 9.0 if possible) in order to run a supercharger. so since i'm gonna get the block bored to probably .030 over i want to put in a different rotating assembly (forged internals) in and i was wondering what would anyone suggest? (not that interested in doing a stroker unless it'll still work fine and not be that much more expensive) an i plan on running a set of AFR 185 heads w/ 72 cc combustion chambers if that'll help.
 

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well the stock motor is pretty low compression as it sits if u are going to supercharge an engine i wouldnt stroke it on a stock block or your asking to split that thing.. u should do one of the two things ither stroke it or supercharge it.. they will each cost about 4k if u do the work yourself....
 

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When i pull my engine to do a rebuild this summer, i want to end up with a low compression ratio (hopefully under 9.5 possibly under 9.0 if possible) in order to run a supercharger. so since i'm gonna get the block bored to probably .030 over i want to put in a different rotating assembly (forged internals) in and i was wondering what would anyone suggest? (not that interested in doing a stroker unless it'll still work fine and not be that much more expensive) an i plan on running a set of AFR 185 heads w/ 72 cc combustion chambers if that'll help.
A stock 5 liter HO engine has 9:1 compression. If you put a 72 cc head on that it will bring it down to about 8:1 which is a little on the low side even with a supercharger.
 

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Discussion Starter #6
A stock 5 liter HO engine has 9:1 compression. If you put a 72 cc head on that it will bring it down to about 8:1 which is a little on the low side even with a supercharger.
so what combustion heads would you suggest? or should i just forget about boring this block an instead go buy an aftermarket shortblock that is already bored with a "stroker" rotating assembly and then put on the 72cc heads.
 

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so what combustion heads would you suggest? or should i just forget about boring this block an instead go buy an aftermarket shortblock that is already bored with a "stroker" rotating assembly and then put on the 72cc heads.
61cc. If you build a 347 get dished pistons and keep the compression around 9:1. I wouldn't worry about an aftermarket block unless you plan on making in excess of 500 horsepower and turning more than 6500 rpm.
 

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Discussion Starter #8
so in reality...i really could just put the s/c on the motor as it is an be fine runnin say 8 or 9 psi. right? cuz my dad said i'd have to rebuild the engine but if i'm understandin you right i don't really have to.
 

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no you dont have to rebuild the engine to run low boost (6-9psi)

and you can run a turbo/supercharged/nitrous injected engine with 10:1 compression
 

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well nitrous isnt really the same as actual boost
 

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ya nitrous can be ran with any compression but yes u can run forced induction on a stock mustang block.. upgrading your heads would be well worth it too..
 

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so in reality...i really could just put the s/c on the motor as it is an be fine runnin say 8 or 9 psi. right? cuz my dad said i'd have to rebuild the engine but if i'm understandin you right i don't really have to.
Correct, no need for a rebuild.
 

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61cc. If you build a 347 get dished pistons and keep the compression around 9:1. I wouldn't worry about an aftermarket block unless you plan on making in excess of 500 horsepower and turning more than 6500 rpm.

^^^^^^
 

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okay, so since i don't have to rebuild. what heads would be best for a 9 psi set up?
Depends on how much money you want to spend on a set of heads.
 

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Some Twisted Wedge or AFR 165s will work for that price range.
 
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